As petroleum products are drained from subterranean formations, the reservoir energy gradually decreases. In some cases, the reduced reservoir pressure allows water to accumulate and “load” the well. Gas wells that are loaded with water tend to produce poorly in intermittent slug flow or cease to produce at all.
Artificial lift and stimulation procedures are often used to increase production from a loaded well. Chemical additives are often used to unload, or “de-water” the well. In recent years, it has become popular to inject “foamer” solutions down a capillary string to aid in the unloading of water accumulated in the wellbore. As gas passes through the foamer and water mixture, bubbles form and lift the water from the well. Foamers, or “soaps,” typically include a surfactant component that reduces the surface tension and fluid density of the water-well fluid mixture in the wellbore.